Tracking animal migration - AbsoluteAstronomy.com

For years scientists have been tracking

Tracking

Tracking can refer to:*Tracking , separating children into different classes according to their academic ability*Tracking, in computer graphics, a vital part of match moving...

animals and the ways they migrate

Animal migration

Animal migration is the relatively long-distance movement of individuals, usually on a seasonal basis. It is a ubiquitous phenomenon, found in all major animal groups, including birds, mammals, fish, reptiles, amphibians, insects, and crustaceans. The trigger for the migration may be local...

. One of the many goals of animal migration research has been, of course, to determine where the animals are going; however, researchers also want to know why they are going "there". Researchers not only look at the animals migration but also what is between point a and point b to determine if a species if moving to new locations based on food density, a change in water temperature, and the animal's ability to adapt to these changes.

Technologies for tracking

In the fall of 1803, American Naturalist John James Audubon

John James Audubon

John James Audubon was a French-American ornithologist, naturalist, and painter. He was notable for his expansive studies to document all types of American birds and for his detailed illustrations that depicted the birds in their natural habitats...

wondered whether migrating birds returned to the same place each year. So he tied a string around the leg of a bird before it flew south. The following spring, Audubon saw the bird had indeed come back.

Scientists today still attach tags, such as metal bands, to track movement of animals. But metal bands are not always useful tags. That is because the tagged animals have to be caught again for the scientists to get any data and the data is limited to the animal's release and destination points. Unfortunately, most tagged animals are never seen again.

Recent technologies have helped solve this problem. Some electronic tags give off repeating signals that are picked up by radio devices or satellite

Satellite

In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....

s while other electronic tags could include archival tags (or data loggers). Scientists can track the locations and movement of the tagged animals without recapturing them using this RFID technology or satellites. These electronic tags can provide a great deal of data. However, they are more expensive than the low-tech tags that aren't electronic. Also, because of their size and weight, electronic tags may create drag on some animals slowing them down.

Radio tracking

Tracking

Tracking can refer to:*Tracking , separating children into different classes according to their academic ability*Tracking, in computer graphics, a vital part of match moving...

an animal by radio involves two devices. A transmitter

Transmitter

In electronics and telecommunications a transmitter or radio transmitter is an electronic device which, with the aid of an antenna, produces radio waves. The transmitter itself generates a radio frequency alternating current, which is applied to the antenna. When excited by this alternating...

attached to the animals sends out a signal in the form of radio waves

Radio waves

Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Radio waves have frequencies from 300 GHz to as low as 3 kHz, and corresponding wavelengths from 1 millimeter to 100 kilometers. Like all other electromagnetic waves,...

, just as a radio station

Radio station

Radio broadcasting is a one-way wireless transmission over radio waves intended to reach a wide audience. Stations can be linked in radio networks to broadcast a common radio format, either in broadcast syndication or simulcast or both...

does. A scientist might place the transmitter around an animals ankle

Ankle

The ankle joint is formed where the foot and the leg meet. The ankle, or talocrural joint, is a synovial hinge joint that connects the distal ends of the tibia and fibula in the lower limb with the proximal end of the talus bone in the foot...

, neck

Neck

The neck is the part of the body, on many terrestrial or secondarily aquatic vertebrates, that distinguishes the head from the torso or trunk. The adjective signifying "of the neck" is cervical .-Boner anatomy: The cervical spine:The cervical portion of the human spine comprises seven boney...

, wing

Wing

A wing is an appendage with a surface that produces lift for flight or propulsion through the atmosphere, or through another gaseous or liquid fluid...

, carapace

Carapace

A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...

, or dorsal fin

Dorsal fin

A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...

. A VHF receiver picks up the signal, just like a home radio picks up a station's signal. The receiver is usually in a truck

Truck

A truck or lorry is a motor vehicle designed to transport cargo. Trucks vary greatly in size, power, and configuration, with the smallest being mechanically similar to an automobile...

, an ATV

All-terrain vehicle

An all-terrain vehicle , also known as a quad, quad bike, three wheeler, or four wheeler, is defined by the American National Standards Institute as a vehicle that travels on low pressure tires, with a seat that is straddled by the operator, along with handlebars for steering control...

, or an airplane. To keep track of the signal, the scientist follows the animal using the receiver. This approach of using radio tracking can be used to track the animal manually but is also used when animals are equipped with other payloads. The receiver is used to home in on the animal to get the payload back.

Satellite tracking

Receivers can be placed in Earth

Earth

Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...

-orbit

Orbit

In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...

ing satellites such as ARGOS . Networks, or groups, of satellites are used to track animals. Each satellite in a network picks up electronic signals from a transmitter on an animal. Together, the signals from all satellites determine the precise location

Location (geography)

The terms location and place in geography are used to identify a point or an area on the Earth's surface or elsewhere. The term 'location' generally implies a higher degree of can certainty than "place" which often has an ambiguous boundary relying more on human/social attributes of place identity...

of the animal. The satellites also track the animal's path as it moves. Satellite tracking is especially useful because the scientists do not have to follow after the animal nor do they have to recover the tag to get the data on where the animal is going or has gone. Satellite networks have tracked the migration of caribou, sea turtles, whales, great white sharks, seals

Pinniped

Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...

, elephants, bald eagles, and osprey

Osprey

The Osprey , sometimes known as the sea hawk or fish eagle, is a diurnal, fish-eating bird of prey. It is a large raptor, reaching more than in length and across the wings...

s. Additionally pop-up satellite tags are used on marine mammals and various species of fish.

Why tracking is important

Electronic tags are giving scientists a complete, accurate picture of migration patterns. For example, when scientists used radio transmitters to track one herd

Herd

Herd refers to a social grouping of certain animals of the same species, either wild or domestic, and also to the form of collective animal behavior associated with this or as a verb, to herd, to its control by another species such as humans or dogs.The term herd is generally applied to mammals,...

of caribou, they learned two important things. First, they learned that the herd moves much more than previously thought. Second, they learned that each year the herd returns to about the same place to give birth

Birth

Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...

. This information would have been difficult or impossible to obtain with "low tech" tags.

Tracking migrations is an important tool to better understand and protect species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

. For example, Florida

Florida

Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

manatees are an endangered species

Endangered species

An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...

, and therefore they need protection. Radio tracking showed that Florida manatees may travel as far as Rhode Island when they migrate. This information suggests that the manatees may need protection along much of the Atlantic Coast of the United States. Previously, protection efforts focused mainly in the Florida area.

Due to the current oil spill, effort in tracking animals has increased in the Gulf. Most researchers who use electronic tags have only a few options: pop-up satellite tags, archival tags, or satellite tags. Historically these tags were generally expensive and could cost several thousands of dollars per tag. However, with current advancements in technology prices are now allowing researchers to tag more animals.

External links

The source of this article is wikipedia, the free encyclopedia. The text of this article is licensed under the GFDL.